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Small-scale, deformable riblets, embedded within the viscous sublayer of a turbulent boundary layer and capable to adapt to the overlying motion, are studied. The wall micro-grooves are made of a linearly elastic material and can undergo small deformations ...
Planetesimal were the first planetary objects to form in the solar system, which later grew to make the proto-planets. Most of these bodies were differentiated as a result of internal heating. Several differentiated bodies have, then, been accreted followi ...
Spin transitions in (Mg,Fe)SiO3 bridgmanite have important implications for the chemistry and dynamics of Earth's lower mantle, but have been complex to characterize in experiments. We examine the spin state of Fe in highly Fe-enriched bridgmanite synthesi ...
We performed laser-heated diamond anvil cell experiments combined with state-of-the-art electron microanalysis (focused ion beam and aberration-corrected transmission electron microscopy) to study the distribution and valence of iron in Earth's lower mantl ...
Recent palaeomagnetic observations(1) report the existence of a magnetic field on Earth that is at least 3.45 billion years old. Compositional buoyancy caused by inner-core growth(2) is the primary driver of Earth's present-day geodynamo(3-5), but the inne ...
Experimental studies at pressure and temperature conditions of the Earth's lower mantle have shown that iron in ferropericlase (Fp) and in Mg-silicate perovskite (Pv) undergoes a spin state transition. This electronic transition changes elastic and transpo ...
Seismic tomography models reveal two large low shear velocity provinces (LLSVPs) that identify large-scale variations in temperature and composition in the deep mantle. Other characteristics include elevated density, elevated bulk sound speed, and sharp bo ...
Recent experimental measurements of the equation of state of perovskites and post-perovskites in the (Mg,Fe)SiO3 and (Mg,Fe,Al)(Fe,Al,Si)O-3 systems over a wide range of iron contents are used to constrain the effects of Fe and Al on density and bulk modul ...
Seismic imaging of the internal Earth has emphasized the inhomogeneity of its mantle. This interface layer of nearly 3000 km surrounding the central metallic core conducts heat released from the latter, which played a significant role in shaping the actual ...
We report ab initio (LDA + U-sc) calculations of thermoelastic properties of ferric iron (Fe3+)- and aluminum (Al)-bearing bridgmanite (MgSiO3 perovskite), the main Earth forming phase, at relevant pressure and temperature conditions and compositions. Thre ...
